Yesterday, we got as far as assembling the stew.
Put it in a gas mark 2/150 C oven, for about two and a half hours. Meanwhile, make the dumplings: stir together the flour and suet with a little salt and pepper, and add enough water (probably about 5 tbsps) to make a pliable dough. Roll the dough between your palms into balls a little larger than golf balls.
Transfer the meat from the stew to a colander over a bowl. Strain the sauce through a sieve into a saucepan, pushing down on the vegetables to extract as many juices as possible, and adding any sauce that drained from the meat. Return the meat to the casserole, and put the lid on.
The sauce may be a little thin. Put the pan on to a moderate heat, letting the sauce bubble until it thickens slightly. Do not be too enthusiastic: you don't want something that congeals on the plate, or that, owing to concentration, has become unbearably salty. Taste it.
When the sauce is ready, pour it over the meat in the casserole. Bring the contents to a gentle simmer, throw in the dumplings, cover, and cook very gently -- either on the hob or in the oven -- for 20 minutes.
You do not need to bring the stew to a simmer before putting it in the oven. The slow rise in temperature is good, because cuts such as chuck steak need very gentle cooking. But, in assessing the timing, you should have a rough idea of how your casserole dish and oven will behave. This stew in my 24 cm Le Creuset takes about an hour to come to simmering point at gas mark 2; but I have a larger, oval Le Creuset that seems to resist heat for a lot longer. Once the stew is simmering, I turn down the oven to its lowest setting.
You could cook the stew on the hob -- but that tends to set it bubbling at a faster rate than is ideal for the care of the meat.
You cover the meat with liquid because it will be cooler in its bath than it would be if exposed to oven heat and steam.
Check the state of the meat from time to time. Do not carry on cooking it after it has become tender.
After two and a half hours, the onion, carrot and celery have given up all their flavours to the stew, and are nutritionally null. I prefer to discard them.
Suet is not as widely available as it used to be. The only stuff I could find was Atora Light vegetable suet. It worked fine. I was less sure about the organic flour I used: it gave a stodgy result, I thought. You could add parsley or other herbs to the dumplings, and/or parmesan cheese; you could enrich the dough with a beaten egg.